Sheet metal container



Dec. 28, 1943.- H. SCHRADER SHEET METAL CONTAINER Filed May 28, 1940 J/VVA'A/TYOI? I F/Mihm M Mm @Zm.

Patented Dec. 28, 1943 UNITED STATES PATENT OFFICE SHEET METAL CONTAINER Herbert Schrader, Wheeling, W. Va., assignor to Continental Can Company. Inc., New York, N. Y., a corporation of New York Application "May 28, 1940,Serial No. 331696 1 Claim. (Cl. 220-59) The invention relates to new and useful improvements in a sheet metal container which is adapted for hermetically packaging food products.

An object of the invention is to provide a slip cover container which is so constructed that the closure member may be tightly secured to the container body so as to hermetically seal the container and at the same time permitting said closure member to be removed without cutting or rupturing the metal of the closure member or the body of the container. A further object of the invention is to :provide a container of the above type which is so constructed that the closure member may be used for re-closing the container after it is removed.

In the drawing- Figure 1 is a view showing in vertical section a container body and a closure member therefor embodying the improvements, th closure member being separated from the body;

Fig. 2 is a detail on a larger scale showing a vertical section through the container and closure member when the closure member is first placed on the container;

Fig. 3 is a view showing the closure member pressed into sealing contact with the container and the initial rolling of the flange of the closure member for securing it to the container;

Fig. 4 is a similar view but showing the flange of the closure member rolled into a bead, which bead is forcibly placed beneath and in contact with the bead on the container body for drawing said closure member into tight sealing contact with the container;

Fig. 5 is a view similar to Figure 2, but showing the closure member in tight sealing engagement with the container body, and

Fig. 6 is a View similar to Figure 5, showing an opening tool applied to the closure member for removing it from the container body.

The invention has to do particularly with a sheet metal container and the method of closing the same. The sheet metal container includes a body portion I having a bottom end 2 joined thereto by a double seam 3 in the usual manner. The upper edge portion of the body wall I is rolled outward, thence downward and inward to provide a hollow head 4.

The closure member for the container is indicated at 5. Said closure member has a centrally disposed depression surrounded by a vertical wall 6. The depending skirt 1 of the closure member is spaced away from the vertical wall 6 so that said skirt and vertical wall are connected by a curved member 8. Between the vertical wall 8 and the skirt 1 is a channel 9 in which is placed a sealing gasket of any suitable construction. The channel 9 is so dimensioned that .it fits down over the bead '4 on the container body with the wall 6 frictionally engaging theinner wall of the container body. The skirt 1 contacts with the extreme outer portion of the bead 4 when the closure member is initiallyplaced on the container as shown in Figure 2. Extending outwardly from the lower edge portion of the depending skirt I is a flange ID, the extreme outer edge portion of which is curled upwardly as in dicated at H.

The container is sealed by placing the closure member on the container so as to bring the gasket into contact with the upper face of the hollow bead 4 "on the container body. A suitable mechanism is provided for tightly securing the closure member to the container body. One form of mechanism for accomplishing this result is illustrated more or less diagrammatically in Figures 3 and 4. The mechanism consists of a chuck l2 which fits within the recess of the container body and is provided with a portion 13 which overlies the curved portion 8 of the closure member. After the container is filled, the closure member is applied thereto in the manner shown in Figure 2, and then the container and closure member are placed on a support in a machine including this chuck l2. The chuck is moved relative to the support for the container until the portion l3 contacts with the curved portion 8 of the closure member, and until sufiicient pressure is applied to move the closure member into tight sealing contact with the gasket and the gasket in turn into tight sealing contact with the upper face of the hollow bead 4. While the closure member is thus held in tight sealing contact with the container, a curling roll I4 is brought into engagement with the initially curled portion II of the flange It. It is understood that either the container or the curling roll will be rotated about the center of the container so that the flange is progressively curled inwardly as shown in Figure 3, and finally pressed beneath the hollow bead on the container body as shown in Figure 4. This is accomplished by the inward movement of the curling roll M. This curling of the flange produces a hollow bead, the inner diameter of which is slightly less than the outer diameter of the hollow bead 4 on the body of the container. As the curling roll forms this bead, it forces the skirt I of the closure member tightly around the bead 4, drawing the closure member into even tighter sealing contact with the gasket. Thus it is that the closure member is drawn into very tight sealing contact with the container body and the container hermetically sealed.

The gasket used in connection with the container may be formed by flowing a sealing compound of the usual type into the channel, and if desired, suitable additional fillers may be embodied therein in order to produce a cushion type of seal, In place of the sealing material, a preformed gasket may be used. v

When it is desired to open the container, a tool such as indicated at I5 may be used. The tool is provided with a slotted end portion providing a curved prying lip 16 and a rounded fulcrum projection I! leading to the curved lip. The tool is placed on the bead formed by rolling the flange [0 of the closure member, and the lip forced in between the bead and the body wall, after which the lever is moved so as to force the bead outward, and by applying this lever at intervals, the bead on the closure member may be expanded so that the closure member can be removed from-the container. This upward pry on the container will also break the vacuum, if the container is under vacuum, so as to permit the closure member to be easily removed. It will be noted that there is no raw edge of metal on the body wall when the closure member is re-- moved; neither is there any raw edge of metal exposed on the closure member. In other words, the closure member is removed from the container and the seal broken without cutting the metal or rupturing the metal in any way. Furthermore, this closure member may be used as a re-closure for the container, as the gasket will stay in place and the closure member may be slipped down into the container body, bringing the gasket into contact with the head on the container body.

The invention as noted above, resides not only in the container, but in the method of closing the container, all of which has been set forth in detail above.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is-- A sheet metal container comprising a cylindrical body portion having the upper edge portion thereof rolled outwardly, downwardly and inwardly into contact with the body wall for forming a closed rigid hollow bead, and a closure member for said container having a depressed central portion providing a vertical wall adapted to frictionally fit within the body and having a depending skirt offset therefrom forming a channel adapted to receive the bead on the body, a sealing gasket in said channel, said skirt being dimensioned and curved to conform to the outer face of the bead and contact therewith to a line at the under side of the bead when the container is closed and sealed, said skirt from said line being curved downwardly, thence outwardly, thence upwardly and inwardly into contact with the outer face of the skirt substantially in the same plane in which the body contacting portion of the first mentioned bead lies for forming a closed continuous rigid hollow bead of substantially the same diameter as the bead on the body wall firmly gripping the head on the container body, said hollow bead on the skirt being spaced away from the body wall a distance of at least half the diameter of the body wall contacting bead and sufliciently to permit a tool to be wedged therebetween for prying the skirt outwardly to release the closure member.

HERBERT SCHRADER. 

